Uplink switching for enhanced mobility

Abstract

This disclosure provides systems, methods and apparatuses, including computer programs encoded on computer storage media, for uplink switching for enhanced mobility. In some aspects, this disclosure provides techniques for potentially reducing or eliminating service interruptions experienced during a handover from a source cell to a target cell. Additionally, this disclosure provides techniques for potentially simplifying or improving uplink communications while a UE is connected to both the source cell and the target cell during the handover. This disclosure further provides techniques for potentially reducing UE power consumption or improving uplink resource utilization during a handover from a source cell to a target cell while a UE is connected to both the source cell and the target cell during the handover.

What is claimed is: 
     
         1 . A method of wireless communication performed by an apparatus of a user equipment (UE), comprising:
 detecting a trigger in association with a handover from a source cell to a target cell,
 wherein the trigger is associated with a radio resource control (RRC) reconfiguration; 
   switching from the source cell to the target cell based at least in part on detecting the trigger,
 wherein the UE is connected to both the source cell and the target cell during the handover from the source cell to the target cell; and 
   releasing physical channel resources associated with the source cell,
 wherein the releasing is associated the handover from the source cell to the target cell. 
   
     
     
         2 . The method of  claim 1 , wherein the trigger is associated with a RRC reconfiguration complete message. 
     
     
         3 . The method of  claim 1 , wherein the trigger is received from the target cell. 
     
     
         4 . The method of  claim 1 , further comprising:
 receiving an indication to release the physical channel resources, wherein the physical channel resources are released based at least in part on the indication.   
     
     
         5 . The method of  claim 4 , wherein the indication is received via RRC signaling. 
     
     
         6 . The method of  claim 4 , further comprising:
 ceasing monitoring and reception of downlink transmissions from the source cell based at least in part on the indication.   
     
     
         7 . The method of  claim 4 , further comprising:
 ceasing sounding reference signal (SRS) transmissions to the source cell based at least in part on the indication.   
     
     
         8 . A user equipment (UE) for wireless communication, comprising:
 a processing system that includes one or more processors and one or more code-storing memories coupling with the one or more processors, the processing system configured to cause the UE to:
 detect a trigger in association with a handover from a source cell to a target cell,
 wherein the trigger is associated with a radio resource control (RRC) reconfiguration; 
 
 switch from the source cell to the target cell based at least in part on the trigger,
 wherein the UE is connected to both the source cell and the target cell during the handover from the source cell to the target cell; and 
 
 release physical channel resources associated with the source cell,
 wherein the release is associated with the handover from the source cell to the target cell. 
 
   
     
     
         9 . The UE of  claim 8 , wherein the trigger is associated with a RRC reconfiguration complete message. 
     
     
         10 . The UE of  claim 8 , wherein the processing system is further configured to cause the UE to:
 receive the trigger the target cell.   
     
     
         11 . The UE of  claim 8 , where the processing system is further configured to cause the UE to:
 receive an indication to release the physical channel resources, and   wherein the processing system, to release the physical channel resources, is configured to cause the UE to:
 release the physical channel resources based at least in part on the indication. 
   
     
     
         12 . The UE of  claim 11 , wherein the processing system, to receive the indication, is configured to cause the UE to:
 receive the indication via RRC signaling.   
     
     
         13 . The UE of  claim 11 , wherein the processing system is further configured to cause the UE to:
 cease monitoring and reception of downlink transmissions from the source cell based at least in part on the indication.   
     
     
         14 . The UE of  claim 11 , wherein the processing system is further configured to cause the UE to:
 cease sounding reference signal (SRS) transmissions to the source cell based at least in part on the indication.   
     
     
         15 . A method of wireless communication performed by an apparatus of a user equipment (UE), comprising:
 receiving a trigger in association with causing the UE to switch from a source cell to a target cell for transmitting communications,
 wherein the trigger is associated with a radio resource control (RRC) reconfiguration; 
   switching from the source cell to the target cell for transmitting communications based at least in part on receiving the trigger,
 wherein the UE is connected to both the source cell and the target cell during a handover from the source cell to the target cell; and 
   releasing channel resources associated with the source cell,
 wherein the releasing is associated the handover from the source cell to the target cell. 
   
     
     
         16 . The method of  claim 15 , wherein the trigger is associated with a RRC reconfiguration complete message. 
     
     
         17 . The method of  claim 15 , further comprising:
 receiving an indication to release the channel resources, wherein the channel resources are released based at least in part on the indication.   
     
     
         18 . The method of  claim 17 , wherein the indication is received via RRC signaling. 
     
     
         19 . The method of  claim 17 , further comprising:
 ceasing monitoring and reception of downlink transmissions from the source cell based at least in part on the indication.   
     
     
         20 . The method of  claim 17 , further comprising:
 ceasing sounding reference signal (SRS) transmissions to the source cell based at least in part on the indication.